Many types of input devices are presently available for performing operations in a computing system, such as buttons or keys, mice, trackballs, joysticks, touch sensor panels, touch screens and the like. Touch screens, in particular, are becoming increasingly popular because of their ease and versatility of operation as well as their declining price. Touch screens can include a touch sensor panel, which can be a clear panel with a touch-sensitive surface, and a display device such as a liquid crystal display (LCD) that can be positioned partially or fully behind the panel so that the touch-sensitive surface can cover at least a portion of the viewable area of the display device. Touch screens can allow a user to perform various functions by touching the touch sensor panel using a finger, stylus or other object at a location dictated by a user interface (UI) being displayed by the display device. In general, touch screens can recognize a touch event and the position of the touch event on the touch sensor panel, and the computing system can then interpret the touch event in accordance with the display appearing at the time of the touch event, and thereafter can perform one or more actions based on the touch event.
Mutual capacitance touch sensor panels can be formed from a matrix of drive and sense lines of a substantially transparent conductive material such as Indium Tim Oxide (ITO), sometimes arranged in rows and columns in horizontal and vertical directions on a substantially transparent substrate. In some touch sensor panel designs, ITO drive and sense lines can be formed on opposite sides of the same substrate in a configuration referred to herein as double-sided ITO (DITO). The substantially transparent drive and sense lines can be routed to one edge of the substrate for off-board connections using conductive (e.g. metal) traces in the border areas of the substrate where transparency is not required. However, it can be expensive to manufacture the one or more flex circuits that are required to provide off-board connectivity for the drive and sense lines.